The Niobrara is a 76-mile National Scenic River that behaves like no other Nebraska river: spring-fed, clear, and cold, running through a valley where six different ecosystems meet. Waterfalls spill off the canyon walls straight into the current — you’ll float past several, including Smith Falls, on a single day trip.
The classic run launches east of Valentine through the Fort Niobrara refuge and the state park, and the water stays swimmable even in August. It’s routinely ranked with the best canoeing and tubing rivers in the country, and because the launch points are spread out, it rarely feels crowded.
Use one of the Valentine outfitters — they’ll shuttle you and rent the boat. Go on a weekday, bring sun protection (there’s no shade on the water), and respect the private landowners along the banks; the river is public, the land mostly isn’t.